The present invention relates to an automatic analysis apparatus, and more particularly, to an automatic analysis apparatus provided with the function of keeping the temperature of a row of reaction containers constant.
In a conventional automatic analysis apparatus, an organic sample such as blood is generally measured by means of a photometer after preparing a reaction solution in which the sample and a reagent interact with each other. Measurements of a sample on a large number of analysis items are, for example, performed by using a discrete-type automatic analysis apparatus in which the reaction solution is generated in the reaction container, which is also used as a photometric cell, for each analysis item.
Reaction of the organic samples needs to be performed at a temperature which is kept constant in the vicinity of 37.degree. C. Accordingly, it has been proposed to employ a constant-temperature water bath as a constant-temperature device and to immerse a row of reaction containers in the constant-temperature water. Such an automatic analysis apparatus is disclosed in the specification of Japanese Patent Laid-Open No. 56-168553.
In the above-described type of conventional automatic analysis apparatus in which the constant-temperature water bath is employed as the constant-temperature device, constant-temperature water is circulated between a constant-temperature water supply portion for supplying constant-temperature water and a bath. This requires much space, and therefore increases the overall size of the analysis apparatus.
Furthermore, it is better that a desk-top automatic analysis apparatus employ a constant-temperature air device in place of the constant-temperature water device. However, since the heat capacity of air is smaller than that of water, it takes a long time (e.g., 30 minutes) for a constant-temperature air bath having a heat block therein to raise the temperature of the solution injected into the reaction containers to 37.degree. C., and this results in a prolongation of the overall analysis time.